Image processing apparatus, and non-transitory computer readable medium for reducing undesirable effect during image capturing

An image processing apparatus includes a receiving unit that receives a first image that is captured with an object irradiated with light from a light irradiating unit and a second image that is captured with the object not irradiated with light from the light irradiating unit, and a generating unit that generates a composite image by adjusting brightness of a whole area of the second image such that brightness at a specific location in the first image is approximately equal to brightness at a corresponding specific location in the second image, and by replacing in the first image a pixel value of a pixel that is affected by light irradiation by the light irradiating unit with a pixel value of a pixel in the second image that has been adjusted in brightness.